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The existing techniques for lignosulfonate (LS) in humate fertilizers lack selectivity to humic substances (HS) as the main component; they involve labor- and time-consuming sample preparation to separate the components at the level of detectable LS concentrations. The procedure based on attenuated total reflectance (ATR) FTIR spectroscopy with simple sample preparation for directly quantifying lignosulfonates in aqueous solutions and lignosulfonates and HS in aqueous solutions of preparations based on HS of coal origin (Sigma Aldrich, Powhumus, and Life Force) was developed. Lignosulfonate quantification is possible by exploiting the bands at 1266, 1192, 1093, and 1042 cm−1 with limits of detection of 0.4–2 g/L. Quantifying LS in a mixture with humates includes centrifugation of prepared solutions to separate interfering silicate impurities. LS quantification in the range of 10–100 g/L against HS (up to a 2-fold excess) with an error of up to 5% is possible based on the spectral absorptions at 1093 and 1042 cm−1. Simultaneous quantification of humate in the mixture with an error of up to 10% is possible by exploiting the bands at 1570 and 1383 cm−1 (carboxylates). The study shows the possibility of determining lignosulfonate against an HS background several times higher than lignosulfonate. The developed technique is applicable for analyzing fertilizers of simple composition and quality control of pure humates used for plant growth. Obtaining the most accurate results needs calibration solutions from the same brands that make up the test mixture.

Five sample-preparation techniques were compared to quantify 31 elements in coal humic substances (HS) by ICP–AES from the viewpoints of complete isolation and speciation of elements. They include, for bulk composition, preparation of an aqueous colloidal HS solution followed by direct injection of the sample without decomposition and ashing followed by metaborate fusion; for element speciation, preparation of an aqueous colloidal HS solution followed by centrifugation and direct analysis without decomposition for water-soluble species; treatment with boiling nitric acid; and microwave-assisted treatment with nitric acid at 250 °C for acid-isolated species. The results of analysis significantly depend on the selected method of sample preparation due to specific features of HS, the simultaneous presence of many inorganic components in wide concentration ranges, and a significant fraction of the organic matrix; therefore, the total mineral composition of HS, both macro- and microcomponents, requires a combination of decomposition methods.

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Binodal curves for aqueous two-phase systems (ATPS) polyethylene glycol 1500 (PEG1500)−sodium sulfate− water with additions of sodium chloride and hydrochloric or sulfuric acids were determined by turbidimetric titration and analysis of coexisting phases. The results are compared with published data for the ATPS PEG1500−sodium sulfate−water without additions, and the influence of additions on the width of the two-phase field, tielines length, and slopes was traced. The influence of initial concentration of palladium, time of phase contact, pH, concentration of sodium chloride and sodium sulfate on the extraction of palladium(II) was studied. The coefficients of distribution of palladium(II) between the phases of ATPS were measured as a function of the concentrations of sodium chloride (0.1, 1.0, and 2.0 mol•L −1 ) and pH values. At lower concentrations of Cl − ions Pd(II) is extracted as a mixture of ions [Pd(H 2 O)Cl 3 ] − and [PdCl 4 ] 2− , whereas the growth of C(Cl − ) leads to prevalence of the latter, which has poorer extraction properties. Maximal values of the distribution coefficient D Pd of about 9.5 ± 0.75 were achieved in the ATPS PEG1500−Na 2 SO 4 −0.1 M HCl and PEG1500− Na 2 SO 4 −(0.05 M H 2 SO 4 + 0.1 M NaCl).

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